#extension GL_OES_EGL_image_external : require
precision mediump float;
varying vec2 textureCoordinate;
uniform samplerExternalOES s_texture;
void main() {
    vec4 rgba = texture2D(s_texture, textureCoordinate);
    float x = textureCoordinate.x;
    if (x <= 0.5) {
        x += 0.25;
    }else{
        x -= 0.25;
    }
    gl_FragColor = texture2D(s_texture, vec2(x,textureCoordinate.y));
}